A particle is defined as a small potion of matter. From its definition, then a single atom can be considered as an atom. This is because an atom is the smallest unit of matter. Also, a molecule can be considered as a particles since it is a small portion of a certain object.
A particle can be a single atom and can also be a molecule.
Further Explanation
Matter
Matter is anything that has weight and occupies space. Matter exists in three states, liquid, gases and solids.
Matter is made up of small particles that are in continuous random movement.
Particles
A particle refers to a single atom or a group of atoms that are bonded together and functions as a single unit.
Therefore, matter is made up of particles which can either be single atoms or chemically bonded atoms to make a molecule. Hence, a molecule is also a particle of matter.
An atom
An atom is the smallest particle of an element that can take part in a chemical reaction.
Atoms are made up of sub-atomic particles which include; protons, neutrons and electrons. When two or more atoms are bonded together they form a molecule.
Molecule
A molecule is the smallest particle of an element or a compound that has similar properties of that particular compound or element.
Molecules could be made up of atoms that are similar such as oxygen molecule or atoms that different from different elements, such as water molecule.
The bonding of atoms to form molecules occurs as a result of sharing or transfer of electrons between atoms.
